But your backend system dont know about this type of activation and everytime VDA VM template image should use workaround if Office 365 Pro Plus should be installed. Now we are suing workaround as described here

If you use a mandatory proxy server in your resource group deployment fails because of missing internet connectivity. There is no chance to deploy the proxy configuration via GPO or login script because deployment didn't start without internet.

It's a good idea to provide a configuration for the machines created from Citrix Cloud to add some important information (proxy settings in that case)